The sliding tongue

[Kern O]

Give me some chunks of aluminum and encouragement from you folks and I go nuts.......

I need to set the trailer up with a sliding tongue because the ramp is so shallow in Maui. When I did the Jupiter that got crushed, I bought a length of 4.5 inch diameter 1/4 wall tubing to do it. They wanted almost as much for 10 feet as they did for the 20 foot length, so I bought the whole thing. I used 10 feet for the Jupiter and had 10 feet left which is going on the new boat. Setting up a sliding tongue means you need to have two support points. One at the front of the trailer and one back about 4 feet.

The first thing I had to do was to install the bow stand. I had made the support plates a couple weeks ago and had them hard anodized. They clamp flat on the trailer's channels, so unless they have 4200 between them and the channels, the water will get in there and rot the channels. So, the first thing you have to do is to put a bead of 4200 on them and bolt them down.

Here is a plate with a bead of my favorite goo on them....



Then I bolted them in place and here's how it looked with the bow stand in place. Yeah, there's 4200 between the stand and the 3/4 inch mount plates. If you look closely, you can see the block that will support the slider tube. It is sitting between the channels but still needed to be cut down to so it would fit all the way to the front of the channels.



OK, here is the really sick piece. Give me a chunk of aluminum and a computer and I go nuts. This is the rear support for the slider tube....




And here it is in place with the tube slid into its final position........

[welder]

KernO , did you pick all them tools up. ?

That is a dang nice fit , Like socks on a rooster !

What coupler/hitch are you using and how are ya pinning the tube to hold it in place [ In and out position ] ?

Purdy work , CNC is neat stuff to play with.

Lester

You should build yourself a cool roll around tool cart/tray , so I don't worry about ya bending over and hurting your back.

[Kern O]

The pins, coupler and what have you will be done in the next few days. This is where electric over hydraulic brakes are great, because there is no actuator on the tongue.

[Daddy'O]

Very impressive Kern O!

Wayne

[jenkinsph]

I have thought about building a trailer with a long telescopic tongue and had considered a square or rectangular tubing. Would require bearings to reduce friction though, have considered Oilite bearings but not the round tongue stock. With a lighter boat about 20 to 23 feet could the tongue be extended a lot further?


Keep up the good work!!


Steve

[Kern O]

Steve: I think you'd want to keep about a 3 to 1 ratio for the overall length of the slider to the span between the bearing points. In my case, I am using a 9 foot tube and my supports are 40 inches apart. Some tube is lost to the coupler mounting and the end stops, but I still will get about 5 feet of extension. My parker 25 used a full 10 feet of tubing and had the supports 3 1/2 feet apart so it extended just over 6 feet. The key is how heavy a tube you'd like to used. I am using schedule 80 stainless pipe. The most significant load comes when you are making tight turns with the trailer. If you have lots of room to turn, the tubing can be lighter.

One of the things I've done that limits the length of the tube is to mount the slider in the center of the channels. The Parker had it mounted under the trailer, so the tube could be longer without potential interference with the bow of the boat. The installation on the Parker was done 8 years ago and the oilite is holding up just fine. The boat is in commercial service and is being launched almost daily.

[Garett]

Now there goes to show yah what a guy can do with the right tools and an idea......Nice work man!

How are you attaching that rear mounting bracket?

[Kern O]

I'll show the final installation in a couple days. Right now, all of the pieces are at anodize. The rear bracket is attached to the flanges of the main channels with 1/2 inch bolts 8 places. The bracket came out a lot more massive than it had to be, but then again, I started with a chunk of aluminum and was only going to keep what was left after machining. The chips are in the scrap bin. If I do another one, I'll thin the walls and flanges down to 3/4" This one has 1" walls. Something that seems like it would be easy has been a challenge every time I've done a sliding tongue. How do you attach a steel coupler to a stainless tube? Yes, it can be welded, but then the weld and the coupler will rust. I want the coupler to be galvanized and mechanically attached to the tube. I finally figured out the right way to do it. Last time, I welded a chunk of steel that was the right diameter for the inside of the tube to the coupler and then had it galvanized. But when I got it back, it was way oversize and would not go together. The galvanize looked like it was put on with a knife and fork. The tube is 4 inches in diameter. The couplers are made to weld onto 3 inch wide rectangular tubing. How do you get there from here?

[jenkinsph]

KernO What are the requirements for the coupler?

I seem to remember some of the pintel hitches were made for pipe for log trucks.
How much checking have you done for a hitch to fit pipe? I can do some looking
for you.

I assume you are planning on a 12,000 to 14,000 lb coupler? Class V ?



Steve


Steve

[welder]

KernO , look up Bulldog ,they have a HEAVY duty coupler tha fits 3" round.

Lester